I was thinking about getting a decent sized air pump to supply my fish room but was not sure what is out there.

I am not educated in what air flow I would need, but more the better as I'd want the capacity to expand if need be. So what the pump will have to keep up to is 15 to 20 tanks with a max water depth of 18" with the main trunk line being roughly 40 to 50 feet. Of course the most quite pump would be ideal seeing as it is in my basement.

Thanks for the help and let me know if I need to provide more info to help the selection process.